Search Results (207)

The objective of this study was the evaluation of fungal solid-state fermentation (SSF) for the production of alginate lyase and extraction of uronic acids from Sargassum sp. For this purpose, the fungi Trichoderma asperellum, Aspergillus oryzae, and Rhizopus oryzae were applied (alone or combined) to Sargassum sp. biomass through SSF (10⁷ spores g_biomass⁻¹, 30 °C, and 7 days of treatment). In general, individual SSF with all three fungi degraded the biomass, achieving a marked synergy in the production of cellulase, laminarinase, and alginate lyase activities (especially for the last one). Trichoderma was the most efficient species in producing laminarinase, whereas Rhizophus was the best option for producing alginate lyase. However, when dual combinations were tested, the maximal values of alginate lyase activities were reached (13.4 ± 0.2 IU g_biomass⁻¹ for Aspergillus oryzae and Rhizopus oryzae). Remarkably, uronic acids were the main monomeric units from algal biomass solubilization, achieving a maximum yield of 14.4 mg_uronic g_biomass⁻¹, with the A + R condition being a feasible, eco-friendly alternative to chemical extraction of this monomer. Additionally, the application of all the fungal pretreatments drastically decreased the total phenolic content (TPC) in the biomass from 369 mg L⁻¹ to values around 44–84 mg L⁻¹, minimizing the inhibition for possible subsequent biological processes in which the residual solid can be used. Full article

In this study, the ultrasonic-assisted extraction of deep eutectic solvents (UADES) for tea polysaccharides was optimized, and their physicochemical properties and antioxidant activities were analyzed. The optimal DES comprised choline chloride (CC) and ethylene glycol (EG) in a molar ratio of 1:3, with a water content of 40%. The optimized condition was an extraction temperature of 61 °C, an ultrasonic power of 480 W, and an extraction time of 60 min. The UADES extraction rate of polysaccharides (ERP) was 15.89 ± 0.13%, significantly exceeding that of hot water (HW) extraction. The polysaccharide content in the UADES-extracted tea polysaccharides (UADESTPs) was comparable to that of hot-water-extracted tea polysaccharides (HWTPs) (75.47 ± 1.35% vs. 74.08 ± 2.51%); the UADESTPs contained more uronic acid (8.35 ± 0.26%) and less protein (12.91%) than HWTP. Most of the UADESTPs (88.87%) had molecular weights (Mw) below 1.80 × 10³ Da. The UADESTPs contained trehalose, glucuronic acid, galactose, xylose, and glucose, with molar ratios of 8:16:1:10. The free radical scavenging rate and total reducing power of the UADESTPs were markedly superior to those of the HWTPs. Moreover, the UADESTPs had a better alleviating effect on H₂O₂-induced oxidative injury in HepG2 cells. This study develops an eco-friendly and efficient extraction method for tea polysaccharides, offering new insights for the development of tea polysaccharides. Full article

Alpinia officinarum Hance exhibits various bioactivities, with polysaccharides being one of its key bioactive components. However, the relationship between the structural characteristics of these polysaccharides and their bioactivities remains unclear and underexplored. In this study, to optimize the extraction process, a Response Surface Methodology-based design combined with single-factor experiments was applied to determine the optimal conditions for the ultrasonic-microwave-assisted extraction of polysaccharides from A. officinarum. The primary structural characteristics and antioxidant activities of two polysaccharide fractions, PAOR-1 extracted by ultrasonic-microwave-assisted extraction and PAOR-2 extracted by hot reflux extraction (HRE), were systematically compared. The optimal extraction conditions, including a liquid–solid ratio of 1:50, extraction time of 19 mins, and ultrasonic power of 410 W, yielded a maximum polysaccharide extraction rate of 18.28% ± 2.23%. The extracted polysaccharides were characterized as acidic polysaccharides with a three-dimensional structure. PAOR-1 and PAOR-2 have different monosaccharide compositions, surface morphologies, and thermal stabilities. The antioxidant activity in vitro studies suggest that PAOR-1 may have higher antioxidant activity than PAOR-2 due to its higher content of uronic acids, lower relative molecular mass, and a more closely packed spatial configuration. These findings provide a theoretical basis for the development and utilization of AOR. Full article

Climate change resulting from human development necessitates increased land use, food, and energy consumption, underscoring the need for sustainable development. Incorporating various feedstocks into value-added liquid fuels and bioproducts is essential for achieving sustainability. Most biomass consists of cell walls, which serve as a primary carbon source for bioenergy and biorefinery processes. This structure contains a cellulose core, where lignin and hemicelluloses are crosslinked and embedded in a pectin matrix, forming diverse polysaccharide architectures across different species and tissues. Nineteen agro-industrial waste products were analyzed for their potential use in a circular economy. The analysis included cell wall composition, saccharification, and calorific potential. Thermal capacity and degradation were similar among the evaluated wastes. The feedstocks of corn cob, corn straw, soybean husk, and industry paper residue exhibited a higher saccharification capacity despite having lower lignin and uronic acid contents, with cell walls comprising 30% glucose and 60% xylose. Therefore, corn, soybeans, industrial paper residue, and sugarcane are more promising for bioethanol production. Additionally, duckweed, barley, sorghum, wheat, rice, bean, and coffee residues could serve as feedstocks for other by-products in green chemistry, generating valuable products. Our findings show that agro-industrial residues display a variety of polymers that are functional for various applications in different industry sectors. Full article

This study aimed to optimize the enzyme-assisted extraction of polysaccharides (RTFPs) from Rosa roxburghii fruit using response surface methodology. Under the optimal extraction conditions, the yield of RTFPs reached 14.02%, which was close to the predicted value of 13.96%. The primary structural characteristics and the antioxidative and immunomodulatory activities of RTFPs were also examined. Structural characterization revealed that RTFPs comprise 36.38% neutral sugar, 48.83% uronic acid, and 7.29% protein. Their heteropolysaccharide structure features two distinct molecular weight fractions (1.87 × 10⁵ Da and 4.75 × 10³ Da) and a monosaccharide composition dominated by glucose (38.93%), arabinose (20.66%), galactose (20.58%), galacturonic acid (10.94%), and xylose (6.52%). Antioxidant assays demonstrated potent radical scavenging activity, with IC₅₀ values of 11 μg/mL (DPPH) and 150 μg/mL (ABTS), comparable to conventional antioxidants. Immunomodulatory studies on RAW264.7 macrophages revealed that RTFPs (100–400 μg/mL) significantly enhanced phagocytosis by 12.61–76.63% and stimulated the secretion of nitric oxide (NO) and tumor necrosis factor-α (TNF-α). These bioactivities are attributed to RTFPs’ high uronic acid content, moderate molecular weight distribution, unique monosaccharide profile, and highly branched conformation. Full article

Microalgae-based bioremediation is increasingly recognized as a sustainable, efficient, and straightforward technology. Despite this growing interest, the potential of Parachlorella hussii for metal biosorption remains underexplored. This study is the first report evaluating the metal biosorption activity in Parachlorella hussii ACOI 1508 (N9), highlighting the impact of the culture age on the monosaccharide composition and its correlation to the metal binding capacity. The capsular strain (N9) was isolated from the hypersaline ecosystem—Lake Chott Aïn El-Beida—in southeastern Algeria. Cultivated in Bold’s Basal medium, the strain produced 0.807 ± 0.059 g L⁻¹ of RPSs and 1.975 ± 0.120 g L⁻¹ of CPSs. Biochemical analysis of the extracts revealed a high total sugar content (% w/w) that ranged from 62.98 ± 4.87% to 95.60 ± 87% and a low protein content (% w/w) that ranged from 0.49 ± 0.08% to 1.35 ± 0.69%, with RPS-D7 and RPS-D14 having high molecular weight (≥2 MDa). HPLC-based monosaccharide characterization demonstrated compositional differences between the exponential and stationary phases, with rhamnose dominating (~55%) in RPS-D14 and with the presence of uronic acids comprising 7–11.3%. Metal removal efficiency was evaluated using the whole biomass in two growth phases. Copper uptake exhibited the highest capacity, reaching 18.55 ± 0.61 mg Cu g⁻¹ DW at D14, followed by zinc removal with 6.52 ± 0.61 mg Zn g⁻¹ DW. Interestingly, removal efficiencies increased to about twofold during the stationary phase, reaching 51.15 ± 1.14% for Cu, 51.08 ± 3.35% for Zn, and 36.55 ± 3.09% for Ni. The positive results obtained for copper/zinc removal highlight the biosorption potential of P. hussii, and notably, we found that the metal removal capacity significantly improved with culture age—a parameter that has been poorly investigated in prior studies. Furthermore, we observed a growth phase-dependent modulation in monosaccharide composition, which correlated with enhanced functional properties of the excreted biomolecules involved in biosorption. This metabolic adjustment suggests an adaptive response that may contribute to the species’ effectiveness in heavy metal uptake, underscoring its novelty and biotechnological relevance. Full article

C. macrophylla and C. tangutorum, collectively known as Shigecai in Chinese, are consumed as special and nutritious vegetables by the Tibetan, Qiang, and Yi communities in China. However, due to the insufficient knowledge of their phytochemical compositions and health benefits, the industrial utilization of these species in the food sector remains limited. Although Shigecai leaves contain substantial pectic polysaccharides, their chemical structures and biological activities remain unknown, which ultimately restricts their industrial utilization. Thus, to address this gap, this study systematically analyzed the chemical characteristics and biological functions of rhamnogalacturonan-I (RG-I)- enriched pectin from C. tangutorum (CTHDP) and C. macrophylla (CMHDP) leaves. The results demonstrate that Shigecai leaves are promising sources of RG-I-enriched pectin, with yields of 57.63–65.21 mg/g dry weight. In addition, both CTHDP and CMHDP exhibited highly similar chemical and structural properties, dominated by RG-I and homogalacturonan (HG) pectin regions, with RG-I ratios of 60.14–63.33 mol%. Furthermore, both samples demonstrated notable antioxidant ability, antiglycation activity, prebiotic potency, and immunoregulatory effects, which were strongly linked to their bound polyphenol content, uronic acid content, and molecular weight. These findings support the industrial utilization of Shigecai and establish Shigecai-derived RG-I-enriched pectin as a promising functional food ingredient. Full article

The ulvans are sulfated heteropolysaccharides that can stimulate the immune response in vitro. Using a human cell model, this study aimed to characterize and evaluate the immunostimulatory properties of crude ulvans extracted from Ulva spp., collected in Algarrobo, Chile. The crude ulvans, characterized by spectrophotometric methods, are composed of 47.6% total sugars, 14.3% uronic acids, and 8.9% sulfates, with an average molecular weight of 40.000 kDa. The FTIR spectrum showed bands related to uronic acids, rhamnose, and sulfate groups. GCMS analysis confirmed the presence of rhamnose, xylose, glucose, and galactose, with a predominance of the disaccharides U3s and B3s. HL60 cells differentiated into macrophages were cultured with three concentrations of crude ulvans (25, 50, and 100 μg/mL), with cell viability remaining above 90% at the lower concentrations. The crude ulvan activated CD86 co-stimulatory molecules and promoted the release of IL-6, IL-10, IL-4, and nitric oxide cytokines. The results suggest that ulvan is non-toxic and can activate inflammatory pathways, making it a potential candidate for studies as a vaccine adjuvant. Full article

The technology of fucoidan extraction significantly affects its properties. This study aimed to evaluate the impact of dynamic maceration (DM) and ultrasound-assisted extraction (UAE) on the antioxidant and anticancer properties of fucoidan from Arctic brown algae. Fucus vesiculosus (Fv), Fucus serratus (Fs), Fucus distichus (Fd), and Ascophyllum nodosum (An) were collected from the Barents Sea. The average yield of fucoidan and uronic acid was higher (by 43.2% and 22.0%, respectively) after UAE, while phlorotannin content decreased by 53.7% compared with DM. The fucose level for all algae increased after UAE, while the molecular weight of fucoidans was lower. The highest antioxidant activity was noted for the fucoidan from An and Fv, which were obtained by DM and can be associated with the high concentrations of phlorotannins. The treatment of HeLa G-63 cells with all studied fucoidans for 48 h increased concentration-dependently the number of dead cells. The most promising were Fv and Fs fucoidans with high phlorotannins, low sulfates, and uronic acid extracted by DM. The co-administration of paclitaxel and fucoidan caused cell cycle arrest in the G2/M phase. The calculated for the first time combinatory effect showed that the simultaneous use of paclitaxel and fucoidan exposure leads to a synergistic interaction. Our results support the rationality of fucoidan use in complex chemotherapy to improve survival, quality of life and immunity in patients with cervical carcinoma. Full article

Lentinan is one of the main metabolites of Lentinula edodes and exhibits numerous biological properties, such as antitumor and antioxidant activity. Despite recent advancements, its commercialization remains constrained by a lengthy cultivation cycle, low yield, and high cost. Therefore, screening strains with high polysaccharide production or enhanced bioactivity at the mycelial fermentation stage is of significant importance. In this study, the mycelial polysaccharide content and in vitro antioxidant activity of 18 L. edodes strains were evaluated under shaking and static culture conditions. The total polysaccharide content and IC₅₀ values under both culture conditions served as indicators for screening high-yielding and high in vitro antioxidant activity strains. Strain XG21 demonstrated superior polysaccharide production, with a total polysaccharide content of 78.80 mg in 50 mL of culture medium, which was 1.82 times higher than that of the main cultivated strain Xin808 (43.30 mg). Additionally, strain XG19 was identified for its high in vitro antioxidant activity, with total IC₅₀ values of 3.11 and 3.38 mg mL⁻¹ under shaking and static culture conditions, respectively. Further analyses on polysaccharide components, molecular weight, and enzyme activities were conducted on strains XG19, XG21, and Xin808. The results reveal that the polysaccharide from strain XG19 exhibited high uronic acid content and a significant weight-average molecular weight. Specifically, the intracellular polysaccharide uronic acid content (2.96%) was 2.22 and 1.14 times higher than that of Xin808 and XG21, respectively, while its weight-average molecular weight (Mw, 702.924 kDa) was 2.60 and 1.28 times greater than that of Xin808 and XG21. While the uronic acid content in its extracellular polysaccharides (EPSs) (8.26%) was similar to Xin808 and XG21, the Mw (83.894 kDa) was 1.56 times greater than that of XG21. Correlation analysis revealed that the content of extracellular polysaccharides and total polysaccharides was positively correlated with phosphoglucose isomerase (PGI) activity but negatively correlated with phosphoglucomutase (PGM) activity. These findings provide valuable strain information for the screening of mycelial polysaccharides with high yields and bioactivities. Full article

Alzheimer’s disease (AD) is characterized by oxidative stress, amyloid-beta (Aβ) deposition, and tau hyperphosphorylation. While polysaccharides have demonstrated anti-AD effects, the properties of Cremastra appendiculata polysaccharides (CAPs) remain underexplored. This study evaluates the physicochemical properties, antioxidant activity, anti-AD effects, and underlying mechanisms of CAP in vitro and in Caenorhabditis elegans (C. elegans) AD models. CAP, containing 22.37% uronic acid, is stable below 270 °C and adopts a triple helix structure. Scanning electron microscopy (SEM) reveals an irregular layered architecture. In vitro, CAP exhibits significant antioxidant activity, protecting PC12 cells from Aβ-induced cytotoxicity. In C. elegans, CAP extends the lifespan in a concentration-dependent manner without affecting growth, alleviating tau-induced locomotor defects, reducing Aβ-induced paralysis and serotonin hypersensitivity, and decreasing Aβ deposition by 79.96% at 2.0 mg/mL. CAP enhances antioxidant capacity and heat resistance by reducing reactive oxygen species (ROS) levels and increasing glutathione S-transferase 4 (GST-4) and glutathione peroxidase (GSH-Px) activities. Additionally, CAP upregulates key genes in the insulin/insulin-like growth factor signaling pathway, including daf-16 and skn-1, along with their downstream targets (sod-3, ctl-1, gst-4, hsp-70). These findings suggest that CAP has potent antioxidant and anti-AD effects, alleviating Aβ- and tau-induced toxicity, and may serve as a promising therapeutic agent for Alzheimer’s disease. Full article

The aim of this study was to investigate the structural characteristics of four polysaccharides derived from Citri grandis fructus immaturus and their antioxidant and expectorant activities. ECP1 fraction passing through a 500 kDa dialysis bag (ECP1A) and ECP2 fraction retained in a 300 kDa dialysis bag (ECP2B) had molecular weights of 340 and 1217 kDa, respectively. All four polysaccharides were composed of six monosaccharides, including l-rhamnose, d-arabinose, d-xylose, d-mannose, d-glucose, and d-galactose, with molar ratios of 1.99:52.38:6.99:2.64:5.15:31.15 for ECP1A and 1.54:65.13:6.34:2.51:3.58:22.07 for ECP2B. ECP1A had an α/β-glucopyranose ring, and the glycosyl groups were linked mainly by 1→4, 1→2, or 1→6 glycosidic bonds. It likely adopted a single-stranded helical conformation. ECP2B had a β-glucopyranose ring, and the glycosyl groups were linked mainly by 1→4, 1→2, or 1→6 glycosidic bonds. Furthermore, in vitro experiments showed that ECP1A displayed excellent antioxidant activity (IC₅₀ = 0.4614 mg/mL). ECP2B significantly inhibited MUC5AC mucin content expression in the mucus hypersecretion model of BEAS-2B cells, thus exerting an expectorant effect. A significant negative correlation was observed between the molecular weight of Citri grandis fructus immaturus polysaccharides and their antioxidant activity, and the uronic acid and d-arabinose contents of these polysaccharides exhibited strong negative trends with both antioxidant and expectorant activities. This study shows the potential for developing and utilizing polysaccharides from Citri grandis fructus immaturus as an antioxidant and expectorant agent. Full article

In this study, figs were dried by hot air drying (HD), vacuum freeze-drying (FD), vacuum drying (VD) and far-infrared drying (FID). Four fig polysaccharides (FPs) were extracted from different dried figs, and the corresponding names were FPH, FPF, FPV and FPFI. The effects of different drying methods on the structural properties, rheological properties and biological activities of FPs were compared. The result shows that the extraction rate of polysaccharides after FD (2.49%) treatment was 58.60%, 50% and 28.35% higher than that of HD (1.57%), VD (1.66%) and FID (1.94%), respectively. Drying methods result in varying molar ratios of monosaccharides. FPFI has more stable gel properties. HD, VD and FID caused damage to the surface structure of the polysaccharides. FPF exhibited the highest uronic acid content (25.56%), along with relatively low apparent viscosity and molecular weight (1.45 × 10⁵ Da), which contributed to its superior antioxidant and lipid-lowering activities. Therefore, FD is a drying method to obtain fig polysaccharide with high antioxidant and hypolipidemic activity. The results provided a scientific basis for the drying process of fig polysaccharide and a reference for the development of potential hypolipidemic products of fig polysaccharide. Full article

The endocarp of Exocarpium Citri Grandis (ECG) is abundant in various bioactive components, such as polysaccharides; however, there are few studies on them. Thus, it is highly necessary to carry out further research on the structural characterization and biological activities of ECG polysaccharides (EPs), which are important bioactive substances. In this study, water-extracted EPs were precipitated by ethanol with final concentrations of 50%, 70%, and 90% (v/v), respectively. Three crude polysaccharides (EP50, EP70, and EP90) were fractioned successively. The three polysaccharide fractions were structurally elucidated and were investigated in vitro for their biological activities related to glucose metabolism containing inhibitory effects on α-glucosidase and non-enzymatic glycosylation and their antioxidant capacities. The main results are summarized as follows: (1) Gradient ethanol precipitation and physicochemical properties of EPs: The yields of EP50, EP70, and EP90 were 11.18%, 0.57%, and 0.18%, respectively. The total sugar contents were 40.01%, 52.61%, and 53.46%, and the uronic acid contents were 30.25%, 18.11%, and 8.17%, respectively. In addition, the three fractions had the same composition of monosaccharides, including rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid, with differences in the content of neutral and acidic monosaccharides. They all may be branched polymers and spherical conformation, and they were acidic polysaccharides containing esterified and non-esterified uronic acids, pyranose-form sugars, and glycosidic linkages of α-configuration and β-configuration, with esterification degrees of 32.25%, 28.82%, and 15.58%, respectively. Meanwhile, EP50, EP70, and EP90 were mainly amorphous, and the molecular conformation in solution was a spherical branching polymer without a triple helix structure. The EPs exhibited excellent thermal stability, with their structures remaining stable below 170 °C. (2) In terms of activity research, the results showed that EPs had a good α-glucosidase inhibitory effect with IC₅₀ values of 1.17 mg/mL, 1.40 mg/mL, and 2.72 mg/mL, respectively, among which EP50 was the best. EP50, EP70, and EP90 displayed antioxidant activity by scavenging DPPH and ABTS radicals as well as oxygen radical absorbance capacity. Among them, EP90 had the strongest antioxidant activity. Furthermore, the EPs showed prominent effects on the inhibitory activity of non-enzymatic glycosylation. In summary, the research on the extraction of polysaccharide from ECG provides a technical reference for the further utilization of ECG resources. This study on antioxidant activity provides theoretical support for their use as a natural antioxidant. As oxidation and glycation are relevant to diabetic complications, the result of this work suggests that EPs may be effective in preventing and treating diabetic complications. Full article

Physalis alkekengi L. fruit polysaccharides can reduce blood sugar, regulate blood lipids, and improve intestinal flora structure. However, the specific polysaccharide components exerting these effects are unclear. In this study, we extracted, separated, purified, and characterized the P. alkekengi polysaccharides Phy-1a, Phy-1b, and Phy-1c. Ion chromatography showed that Phy-1b was mainly composed of rhamnose, arabinose, galactose, glucose, and xylose at a molar ratio of 3.0:19.8:47.5:20.9:8.8, and Phy-1c was composed of rhamnose, arabinose, galactose, glucose, xylose, mannose, ribose Galactosamine hydrochloride and Glucosamine hydrochloride at a molar ratio of 10.4:7.9:22.8:30.5:4.6:4.4:19.4:3.9:5.8. Neither of these polysaccharides contained uronic acid, indicating their neutral property. Methylation analysis and nuclear magnetic resonance spectroscopy showed that Phy-1b was mainly composed of terminal sugars (1-Araf); 1,5-Araf; 1,4-Xylp; 1-Glcp; 2,4-Rhap; 1,3-Glcp; 1,4-Galp; 1,4-Glcp; 1,3-Galp; 1,6-Glcp; 1,3,6-Glcp; and 1,4,6-Galp at a molar ratio of 5.2:7.1:7.8:13.7:6.3:11.2:7.0:16.3:7.4:6.0:6.8:5.3, with the main chain being →2)-α-L-Rhap-(1→4)-β-d-Galp-(1→4)-β-d-Galp-(1→[3)-β-d-Glcp-(1]2→3)-β-d-Glcp-(1→[4)-β-d-Glcp-(1]2→ and the branched chains being β-L-Araf-(1→5)-β-L-Araf-(1→, β-d-Glcp-(1→4)-β-d-Xylp-(1→ 3)-β-d-Galp-(1→, and β-d-Glcp-(1→6)-β-d-Glcp-(1→. The three fragments, respectively, pass through the O-4 key of →2,4)-α-l-Rhap-(1→, O-6 key of →4,6)-β-d-Galp-(1→, and O-6 of →3,6)-β-d-Glcp-(1→ connected to the main chain. These results provide a reference for enhancing the utilization value of P. alkekengi resources to promote its high-value and efficient processing. Full article